Poisson

class superglm.Poisson

Bases: object

Poisson distribution. V(mu) = mu.

variance(

mu: NDArray,

) → NDArray

V(μ) = μ.

variance_derivative(

mu: NDArray,

) → NDArray

V’(μ) = 1.

variance_second_derivative(

mu: NDArray,

) → NDArray

V’’(μ) = 0. Wood (2011) Appendix D.

deviance_unit(

y: NDArray,

mu: NDArray,

) → NDArray

Unit deviance: 2[y log(y/μ) - (y - μ)].

log_likelihood(

y: NDArray,

mu: NDArray,

weights: NDArray,

phi: float = 1.0,

) → float

Poisson log-likelihood (φ fixed at 1).